Q3 2009 Browser Security Tests Published

Today we published our 2nd round of live browser security tests. Two separate tests measured protection against phishing and socially engineered malware across 5 browsers: Apple Safari 4, Google Chrome 2, Mozilla Firefox 3, Opera 10 Beta and Windows Internet Explorer 8.

A key take away is that while the other browsers maintained or decreased protection between the two tests, Internet Explorer continued to improve its protection against cybercriminals.


Socially engineered malware is the most common and impactful threat on the Internet today, with browser protection averaging between 1% and 81%. Internet Explorer 8 caught 81% of the socially engineered malware sites over time, leading other browsers by a 54% margin. Safari 4 and Firefox 3 caught 21% and 27% respectively, while Chrome 2 blocked 7% and Opera 10 Beta blocked 1%.


Phishing protection over time varied greatly between 2% and 83% among the browsers. Statistically, Internet Explorer 8 at 83% and Firefox 3 at 80% had a two-way tie for first, given the margin of error of 3.6%. Opera 10 Beta, exhibited more extreme variances during testing and averaged 54% protection. Chrome 2 consistently blocked 26% of phishing sites, and Safari 4 offered just 2% overall protection. Firefox 3.5 crashing issues prevented it from being tested reliably.

The full text and analysis of these and other reports on browser security can be found at http://nsslabs.com/browser-security.

NSS Labs live testing methodology represents an accurate, real-world testing that can be performed on information security products.

- Newly discovered malicious phishing and malware sites were added to the test, which repeated every four hours 24x7 for a minimum of 12 days

- All five browsers tested URLs simultaneously

- All sites were validated before, during and after via multiple methods